Flow-rate-responsive control means



June 27, 1939. w. R. PERRY FLOW-RATE-RESPONSIVE CONTROL mums Filed Feb.29, 1936 @L? x w.

INVENTOR.

Ilia/n. Parav @676. ATTORNEYS.

Patented June 27, 1939 PATENT OFFICE FLOW-RATE-RESPONSIVE CONTROL MEANSWilliam R. Perry, Columbus, Iiid., assignor to Reeves Pulley Company,corporation of Indiana Columbus, Ind., 8.

Application February 29, 1936, Serial No. 66,501

\ 12 Claims. The present application relates to a flow-rateresponsivecontrol means, and more particularly to an organization which, inresponse to variations in the rate of flow of a controlling liquid,

5 will vary the rate of operation of a given machine. The primary objectof the present invention is to provide a mechanism which will operate tosupply chemical to a. flowing liquid at varying .rates, depending uponthe rate of how of the liquid. More specifically, the primary object ofthe invention is to provide mechanism, responsive to the rate of flow ofsewage, to supply to the flowing sewage chemicals at a. rateproportional to the rate of flow of the sewage. A further object of theinvention is to provide mechanism for automatically adjusting the speedratio between the input shaft and the output shaftof a variable speedtransmission, in accordance with variations in the rate of flow ,of aflowing liquid. Further 20 objects of the invention will appear as thedescription proceeds.

To the accomplishment of the above and related objects, my invention maybe embodied in the form illustrated in the accompanying drawing,

25 attention being called to the fact, however, that the drawing isillustrative only, and that change may be made in the specificconstruction illustrated and described, so long as the scope of theappended claims is not violated.

30 The single figure is a diagrammatic illustration of my control means,connected to control the operation of a variable speed transmission inaccordance with the rate of flow of liquid through a Venturi tube.

35 In the drawing, I have illustrated a venturi tube indicated generallyby the reference numeral I, and comprising the usual inlet portion 2,throat 3, and outlet 4. Associated with said Venturi tube is a diaphragmhousing which is formed to pro- 40 vide a chamber communicating, througha conduit E, with the venturi inlet 2; and a second chambercommunicating, through the conduit 1, with the venturi throat 3; saidtwo chambers being separated by a flexible and fluid tight dia- 45,phragm. Operatively connected to the dia-' phragm is a pull rod 8 whichis suitably connected to one'arm 9 of a bell crank lever iii, the otherarm ll of which carries a weight I2; said lever [0 being mounted, as atl3, 'for oscillation about 50 a fixed pivot point. Said lever ll!further carries a cam l4.

The lever assembly is suitably supported upon a standard I 5 on which ispivotally mounted, as at it, a. lever ll carrying a roller 48 which isoperatively engaged by the cam l4. At its other end,

the lever l1 carries a grooved segmental member is to one end of whichis attached a cable 20 supporting a weight 2i. To the other end of saidsegment is secured a cable 22 which is connected to one arm of a lever23 carrying, at its 5 opposite end, an adjustable weight 24. Said arm 23is pivoted, intermediate its ends, and carries the insulated swingingcontact arm 25 of a potentiometer indicated generally by the referencenumeral 26. Said contact arm is, of course, adapted to sweep theresistance coil 21 of said potentiometer. The ends of the coil 21 arerespectively connected to terminals 42 and 43; and the contact arm 25 isconnected to a terminal 44, through the usual flexible lead. The cam I4is so contoured as to cause the arm 25 to move in increments directlyproportional to incremental variations in the flow rate through theventuri I.

It will be obvious that, as the flow rate through the venturi ldecreases, the diaphragm and its connected push rod 8 will tend to riseto swing the arm in a counterclockwise direction; and,

as the flow rate through the venturi increases, the

diaphragm and its connected rod 8 will tend to move downwardly to swingthe arm 25 in a clock- 25 wise direction over the coil 21.

The reference numeral 28 indicates generally an enclosed variable speedtransmission of the well known Reeves type. Said transmission comprisesa constant-speed shaft 29 which is 30 driven, through a belt or othersuitable driving means 30, by a motor 3| mounted upon the housing ofsaid transmission. The variable speed shaft 32 of said transmission isconnected, by a belt or other suitable driving means 33, to drive 35 adirect current generator 34 of the type which is provided with permanentmagnet fields and which, therefore, delivers a direct current voltagewhich is directly proportional to its speed of rotation. Hereafter, saidgenerator 34 will be referred was a generator.

Likewise mounted upon the housing of the transmission 28 is reversibleelectric motor 35,

' connected, through a belt or other suitable driving means 36, to drivethe screw shaft 3! of the transmission 28, said screw shaft beingarranged, in accordance with standard practice, to shift the elements ofthe transmission 28 to vary the output speed of the transmission. Saidshaft 31 is connected, by a belt or other suitable driving means 38, todrive the shaft 39 of a limit switch 40 connected in the energizingcircuit for the motor 35; so that, as the motor 35 drives the shaft 31,the shaft 39 will likewise be driven to break the energizing circuit forthe motor 35 at either limit of practical operation of the shaft 31 toprevent damage to the transmission 28 Operation of the motor 35 is underthe domination of relay mechanism mounted in a cabinet 41; and, in turn,operated in accordance with Line wires 45 and 46, carrying alternatingcur' rent, supply a transformer 61, the secondary winding of whichimpresses a reduced voltage alternating current upon a dry metallic disctype rectifier 48. Said line wires also supply the same alternatingcurrent to a'second transformer 49, the secondary winding of whichsupplies a reduced voltage alternating current to'a second rectifier 50.

The output direct current voltage of the rectifier G8 is impressedacross the coil 21 of the potentiometer 26 through wires 5| and 52,connected to terminal 42, and wire 53, connected, through a rheostat 55,to terminal 43; the rheostat 54 being manually adjustable to vary thevoltage impressed upon the coil 21. As is clearly shown in the drawing,the wire 55 is connected to the positive output terminal of therectifier 88, so that the terminal 32 will be of positive polarity withrespect to all points along the coil 21. It will therefore be apparentthat the terminal M will be of positive polarity with respect to thewire 55 which is connected to the terminal 64 of the potentiometer 26;and that the voltage measured between the wires 52 and 55 will be theoutput voltage of the potentiometer.

The positively polarized lead 56 from the genorator 3 5 is connected, at5?, with the positive wire 5i of the potentiometer circuit. The negativelead 58 of the generator and the negative output lead 55 of thepotentiometer are connected together, in series with the'movable coil 53of a permanent magnet type galvanometer, and

through the coils i5 3 and iii of a resistor, the wire being connectedto one end of the coil iii by a wire ii,2,'the opposite end of said coil6i being connected to one end of the coil 66 through a wire 63, theopposite end or the coil 56 being connected to one end of the coil 59through a wire 3d, and the opposite end of the coil 59 being connectedto the wire 58.

Since the wires 56 and 52 are connected together at 51, difierences inthe output voltages which is connected to the resistors 60 and SI.

Wire 69 leads from the resistor 60 to one end of a coil 10 which, at itsopposite end, is connected by a wire H to the contact point 66. Wire 62leads from the resistor 6| to one end of a coil 12, the opposite end ofwhich is connected by a wire 13 to the contact point 61. A wire 13'connects the negative terminal of the rectifier 50 with galvanometerneedle 65. Thus, when the galvanometer needle 65 is turned to makecontact with the contact point 66, the coil 10 will be energized; andwhen said needle is turned to make contact with the contact point 61,the coil 12 will be energized.

As has been said, an increase in the flow rate through'the venturi Iwill swing the arm in a clockwise direction to increase the outputvoltage of the potentiometer 26. Assuming that, before such increase,the organization has been in balanced operation, such increase in theoutput voltage of the potentiometer will cause a current fiow throughthe coil 59 in such a direction as to swing the galvanometer needle 65into contact with the contact point 66, thus energizing the coil "I0.Such energization of the coil 10 will shift contact element '74 out ofcontact with element 15 and into contact with element 16, thusclos'ingan energizing circuit for the motor which may be traced as follows: linewire 45, wire 11, wire I8, contact element l9, contact element 80, wireBl, contact element 14, contact element 76, wire 62, limit switch E0,wire 83, motor 35, common lead 8d, limit switch 656, wire 85, and linewire 46. Energization of the motor 35 through the abovetraced circuitwill cause operation of said motor in'such a direction as to increasethe speed of the output shaft 32 of the transmission 28.

Conversely, when a decrease in the ilow rate through the venturi lcauses counterclockwise movement of the arm 25, the output voltage ofthe potentiometer will be decreased, so that the output voltage of thegenerator 3 2 will exceed the output voltage of the potentiometer, and acurrent will flow through the coil 59 in such a direction as to swingthe galvanometer needle 65 into contact with the contact point 6?, soenergizing coil it. Such energlzation of the coil 72 will shift thecontact element 86 into contact with element 86 to close a circuit whichmay be traced as follows: line wire 35, wire Tl, wire 87, contact 15,contact id, wire 81, contact 30, contact 35, Wire 83, limit switch 65,wire 89, motor 35, common wire 84, limit switch id, wire 65, and linewire it. Energization of the motor 35 through the last-traced circuitwill cause operation of the motor in the opposite direction to reducethe speed of the output shaft 32 of the transmission 28.

As has been shown, an increase in the rate of.

fiow of liquid through the venturi I will result in an increase in thespeed of the shaft 32, by operation of the motor 35. As the speed of theshaft 32 increases, the speed of the generator 34 will likewise beincreased to increase the output voltage thereof; and, when the outputvoltage of the generator 34 reaches a value equal to the output voltageof the potentiometer, in its momentary setting, the needle 65 will bereturned to neutral position, thereby deenergizing the motor 35.Similarly, when the motor 35 is'energized to reduce the speed of theshaft 32 as a result of a decrease in the flow rate through the venturiwhich causes a decrease in the output voltage of the potentiometer 26,the motor 35 will continue to operate only until the speed of thegenerator 34 has been reduced sufiiciently to reduce the output voltagethereof to a value equal to the output voltage of the potentiometer.

Reference has been made to the resistors 60 and 6!; but nothing has beensaid about their function. It will be remembered that both of saidresistors are connected in series with the galvanometer coil 59 in theenergizing circuit for said coil. When the galvanometer coil 59 isenergized to swing the needle 65 into contact with one 01' itsassociated contact points, as, for instance, the point 56, a currentwill flow in a circuit including the resistor 60; said current havingits source at the rectifier 50. That current flow develops a voltageacross the resistor 60, which voltage increases the intensity of thecurrent flowing through the galvanometer coil 59, thereby tending topull the galvanometer needle 65 more firmly into contact with thecontact point 66. Conversely, when the coil 59 is energized to swing theneedle into contact with the contact point 61, a voltage is developedacross resistor 6|, which again increases the intensity of the currentflowing through the coil 59. Obviously, the current-flow increaseeffected by the development of voltage across the resistor 61 is in adirection opposite to the current increase resulting from thedevelopment of voltage across the resistor 60; but in either case, thetendency of the voltage development across the energized resistor is toincrease the intensity of the current flowing through the coil 59.

When the generator 34 reaches its new optimum speed, after operation ofthe motor 35 in one direction or the other, to cause the needle 65 toswing out of contact with the contact point 66 or the contact point 51,the current flow from the rectifier 50 through the resistor 60 or' 6| immediately stops, thus removing the additive effect of said resistors tothe current intensity through the coil 59, and permitting the needle 65to move far. her away from the contact point with which it has been incontact, to guard against reclosin of the relay circuit as a result ofmechanical 1 vibration, or the like.

Bridged across the coil 10 is a resistor 90 for the suppression ofarcing at the contact point 85; and a similar resistor 91 is bridgedacross the coil 12.

If it is desired to change the relation of speed of the shaft 32 to flowrate through the venturi i, such a change may be efiected by manual ad-,iustment of the rheostat 54, whereby the speed of the shaft 32 withrelation to a given mechanical position of the contact arm 25 will bevaried.

I claim as my invention:

1. In combination, a conduit, means in said conduit for creating a headdifferential in fluid flowing through said conduit, an electricgenerator, means including a variable-speed transmission for drivingsaid generator, and means dominating said transmission and jointlyresponsive to variations in said head differential and in the voltageoutput of said generator for controlling the speed of said generator inaccordance with the rate of flow of fluid through said conduit.

2. In combination, a variable speed trans mission, a reversible electricmotor operable, upon energization, to vary the output speed of saidtransmission, a circuit for energizing said motor, switch meanscontrolling said circuit, a conduit, means responsive to variations inthe rate of flow of fluid in said conduit to close said switch means toenergize said motor, and means responsive to variations in the outputspeed of said transmission as a result of operation of said motor toopen said switch means to deenergize said motor.

3. In combination, a variable speed transmission, a reversible electricmotor operable, upon energization, to vary the output speed of saidtransmission, a circuit for energizing said motor to run in onedirection, a second circuit for energizing said motor to run in theopposite direction, switch means controlling said circuits,

a conduit, and means for controlling said switch means, comprising apermanent-magnet-type galvanometer, circuits for energizing the coil ofsaid galvanometer to swing in opposite directions to open and closerelay circuits dominating said switch means, means for impressing uponsaid coil a voltage of a value varying directly in response to the rateof flow of fluid through said conduit, and means for impressing uponsaid coil a bucking voltage of a value varying in response to the outputspeed of said transmission.

4. In combination, a variable speed transmission, a reversible electricmotor operable, upon energization, to vary the output speed of saidtransmission, a circuit for energizing said motor to run in onedirection, a second circuit for energizing said motor to run in theopposite direction, switch means controlling said circuits, a conduit,an delectric means for controlling said switch'means, said last-namedmeans comprising means developing a voltage variable in accordance withthe rate of flow of fluid through said conduit, and means for generatinga voltage bucking said first-mentioned voltage and variable inaccordance with the output speed of said transmission.

5. In combination, a conduit, a variable speed transmission, and meansfor controlling the output speed of said transmission in accordance withthe rate of flow of fiuid through said conduit, comprising a reversibleelectric motor operable, when energized to run in one direction, toincrease said output speed and, when energized to run in theoppositedirection, to decrease said output speed, energizing circuitsfor said motor, a magnetic switch controlling each of said circuits, anelectrically-operated two-way switch controlling circuits foralternatively energizing said magnetic switches, means responsive to therate of flow of fluid through said conduit to impress a variable voltageupon said electricallyoperated switch, and means responsive to theoutput speed of said transmission to impress a bucking variable voltageupon said electricallyoperated switch.

6. In combination, a conduit, a variable speed transmission, and meansfor controlling the output speed of said transmission in accordance withthe rate of flow of fluid through said conduit, comprising a reversibleelectric motor operable, when energized to run in one direction, toincrease said output speed and, when energized to run in the oppositedirection, to decrease said output speed, energizing circuits for saidmotor, a magnetic switch controlling each of said circuits, circuits foralternatively energizing said magnetic switches, anelectrically-operated twoway switch controlling said last namedcircuits, a circuit including a potentiometer and said electrically-operated switch, said potentiometer having a movable arm, anoppositely-polarized circuit including a variable-voltage generator andsaid electrically-operated switch, means for positioning the movable armof said potentiometer in accordance with the rate of flow of fluidthrough said conduit, and means connecting the output shaft of saidtransmission to drive said generator.

'7. In combination, a conduit, a variable speed transmission, and meansfor controlling the output speed of said transmission in accordance withthe rate of flow of fluid through said conduit, comprising a. reversibleelectric motor operable, when energized to run in one direction, toincrease said output speed and, when enererator for impressing a buckingvariable volt-,

age upon said electrically-operated switch, means for varying the outputvoltage of one of said voltage-impressing means in accordance with therate of flow of fluid through said conduit, and means for varying theoutput voltage of the other of said voltage-impressing mean inaccordance with the output speed of said transmission.

8. In a device of the class described, a conduit, a variable-speedtransmission, a potentiometer having a contact arm, means operable toshift said contact arm and to hold the same in various predeterminedpositions in accordance with the rate of flow of fluid through saidconduit, means responsive to the position of said contact arm to controlthe output speed of said transmission, so that each position of said armresults in a predetermined output speed of said transmission, and meansfor varying the relation between the position of said arm and the outputspeed of said transmission.

9. In combination, a Variable speed transmission, a reversible electricmotor operable, upon energization, to vary the output speed of saidtransmission, a circuit for energizing said motor to run in onedirection, a second circuit for energizing said motor to run in theopposite direction, switch means controlling said circuits, a conduit,and means for controlling said switch means, comprising apermanent-magnettype galvanometer, circuits for energizing the coil ofsaid galvanometer to swing in opposite directions to open and closerelay circuits dominating said switch means, means for impressing uponsaid coil a voltage of a valve varying in accordance with the rate offlow of fluid through said conduit, means for impressing upon said coila bucking voltageof a value varying in accordance with the output speedof said transmission, and means adjustable to vary the voltage developedby any given rate of flow of fluid through said conduit.

10. In combination, a" variable speed transmission, -a reversibleelectric motor operable, upon aileaoie energization, to vary the outputspeed of said transmission, a circuit for energizing said motor to runin one direction, a second circuit for energizing said motor to run inthe opposite direction, switch means controlling said circuits, aconduit, and means for controlling said switch means, comprising apermanent-magnet-type galvanometer, circuits for energizing the coil ofsaid galvanometer to swing in opposite directions to open and closerelay circuits dominating said switch means, means for impressing uponsaid coil a voltage of a value varying in accordance with the rate offlow of fluid through said conduit, means for impressing upon said coil2. bucking voltage of a value varying in accordance with the outputspeed of said transmission, and means adjustable to vary preliminarilythe voltages developed by one of said voltage-impressing-means. 11. Incombination, a conduit, means in said conduit for creating a headdifierential in fluid flowing through said conduit, a machine, meansincluding a variable-speed transmission for driving said machine, anelectric generator driven at variable speeds through said transmission,and means dominating said transmission and responsive jointly tovariations in said head difierential and in the voltage output of saidgenerator for controlling the output speed of said transmission inaccordance with the rate of fiow oi fluid in said conduit, whereby thespeed of said machine and of said generator will be controlled.

12. In combination, a variable speed transmission, a reversible electricmotor operable, upon energization, to vary the output speed of saidtransmission, a circuit for energizing said motor to run in onedirection, a second circuit for energizing said motor to run in theopposite direction, switch means controlling said circuits, a conduit,and means for controlling said switch means, comprising apermanent-magnet-type galvanometer, circuits for energizing the coil ofsaid galvanometer to swing in opposite directions to open and closerelay circuits dominating said switch means, means for impressing uponsaid coil a. voltage of a value varying in accordance with the rate offlow of fluid through said conduit, an electric generator driven atspeeds variable in accordance with the output speed of said transmissionfor impressing upon said coil a bucking voltage of variable value, andmeans adjustable to vary the voltage developed by any given rate of flowof fluid through said conduit. WILLIAM R. PERRY.

CERTIFICATE OF CORRECTION.

Patent No 2, l6l ,0l9

June 27, 19 590 WILLIAM R. PERRY.

It is'here'by certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 3,0nd. column, line 19, claim for "an delectric" read and electric;column, line 15, claim 9, for the word "valve" read value; said LettersPatent should be read with this correction therein same may conform tothe record of the case in the Patent Office and sealed this 8th day ofAugust,

1 first that the that the Signed (Seal) and A. D. 19 9 Leslie Frazer,

Acting Commissioner of Patents.

